Words of the Day: Bandwidth, MHz, and Mbps

You’re the decision maker.You’re talking to contractors about cost, timing, performance, future scalability and a dozen other factors that need your yes or no. Along the way, you are learning a new language: “cable-ese” that describes the world of data transmission. Do you know bits from bytes? CAT5 from CAT6? RJ-45 from RJ-48?

Our clients are often confused about the term “bandwidth.”What exactly is bandwidth? How is it measured? What difference does it really make in the performance of the network?

To start the conversation, let’s look at three abbreviations that aren’t quite self-evident, yet increasingly ubiquitous in ordinary discourse: Mbps, Gbps and MHz.

Mbps = Mega (“million”) bits per second. A Kilobit would then be one thousand bits per second and the mighty Gigabit signifies one billion bits per second. From there we have the Terabit (one trillion bits), all the way up to one septillion bits (referred to by almost no one as a Yottabit).

Hang on now, what exactly is a “bit?” Good question. A bit is theoretically the smallest indivisible component of information there is. It’s the difference between “on” and “off,” or “1” and “0.” Computers all talk to each other with this handy digital language coded in only two characters, 1 and 0. An example; if a computer wants to count from zero to five, it would do this: “0000, 0001, 0010, 0011, 0100, 0101.”

Back to bits per second. As you can see, it takes quite a lot of bits to communicate any useful information. One megabit per second means that one million bits are whizzing from one device to another every second, using either the atoms of a copper wire or pulses of light in a fiber optic cable as a superhighway.

Now on to Megahertz. Yes, we’re talking about one million hertz here. The term refers to the rate at which a wave moves along from one point to another. If you are on the beach counting one wave per second splashing your toes, you could say that the ocean is doing its thing at 1 hertz, or one wave per second. We can’t imagine the ocean going at one million waves per second. An ocean going at one MHz would be a sight to see, although probably just a blur.

Now consider an ocean of bits, ones and zeroes, instead of water molecules. Of course it’s not that simple, but bear with us. Now cram that seawater into a pipe. waves of bits are coursing through it. You can measure the capacity of the pipe in Hertz AND bits per second.

Bandwidth refers, then, to the complex interaction between bits and hertz that carry information from one place to another. The pipes are, of course, your cables full of conductive material carrying vast amounts of information like electromagnetic plumbing. Oh, and radio-wireless devices can provide a way to transmit information too.

The official dictionary definition of bandwidth is:

“The transmission capacity of an electronic communications device or system; the speed of data transfer.”

So there’s a start, but as any cable technician can tell you, there’s a lot more that factors into the overall setup and running of a cable network. There are issues of signal loss, crosstalk, faulty cables, inadequate software, distance-related attenuation…

We’re NetQ, a cabling provider for both public and private organizations. Delivering bandwidth is our purpose in life. We’d love to help you figure out your next network infrastructure project! We’ve answered a lot of questions over the years, so chances are we can answer yours.